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CVE-2026-53710Suited to automated attack · CISA

MCP Context Forge: RestrictedPython sandbox bypass via getattr builtin in python_sandbox_server

CVSS score

10.0

EPSS probability

%1.1

Risk score

0.1

Published

1 mo ago

Official patch verified

Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2026-53710 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

MCP Context Forge is an AI gateway, registry, and proxy for MCP, A2A, REST, and gRPC APIs. Prior to 1.0.2, the python_sandbox_server in mcp-servers/python/python_sandbox_server/src/python_sandbox_server/server_fastmcp.py exposes raw getattr through safe_builtins, omits a required _getattr_ guard, and relies on validate_code checks for literal dangerous dunder strings. An attacker can construct dunder names at runtime, traverse the Python class hierarchy, reach subprocess.Popen, and execute OS commands with the server process privileges through the execute_code MCP tool. The HTTP/SSE transport can expose this tool without authentication, while stdio-only deployments have reduced network reachability. The issue affects the python_sandbox_server subproject and does not directly affect the core Context Forge gateway or proxy components. This issue is fixed in version 1.0.2.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-53710 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1ibmmcp-context-forge View
2pypimcp-contextforge-gateway View
3pypimcp-contextforge-gateway View
4pypimcp-contextforge-gateway View
Total affected vendors: 2|Products: 4

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
10.0CVSS V3_1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HCVE CNA
10.0CVSS 3.x—Vector not publishedGitHub Advisory
10.0CVSS V31CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HNVD
0.0CVSS 4.0—Vector not publishedGitHub Advisory

Patch and Remediation Guide

Solution & Remediation Advisory

Patch verified

2 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

osvmcp-contextforge-gateway1.0.2

OSV düzeltilmiş sürüm: 1.0.2

gitlabpypi/mcp-contextforge-gateway1.0.2

GitLab Advisory düzeltilmiş sürüm: 1.0.2

gitlab

Upgrade to version 1.0.2 or above.

canonical

Upgrade to version 1.0.2 or above.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-53710 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-53710 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

10.0 / 10
Attack VectorNetworkComplexityLowPrivilegesNoneUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Yama doğrulandı

2 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

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Weakness Type (CWE & CAPEC)

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